The regulator said that upon preliminary review, it found that the new drug application for AXS-14 was not sufficiently complete to permit a substantive review.

Shares of Axsome Therapeutics, Inc. (AXSM) slumped 3% in the pre-market session on Monday after the company said that it has received a Refusal-to-File (RTF) letter from the U.S. Food and Drug Administration (FDA) regarding its application for a drug approval to treat fibromyalgia.

The FDA issues refuse-to-file letters if it identifies deficiencies in a company’s application for drug approval.

The agency said that upon preliminary review, it found that the new drug application for AXS-14 was not sufficiently complete to permit a substantive review.

The FDA noted that it does not consider the second of the two placebo-controlled trials in the submission to be adequate and well-controlled because its primary endpoint was at eight weeks, and it used a flexible-dose paradigm.

The agency, however, opined that the first of the two placebo-controlled trials in the submission, which utilized a 12-week endpoint and a fixed-dose paradigm, is adequate and well-controlled. Both studies yielded positive results.  

To address the FDA’s feedback, Axsome will conduct an additional controlled trial, utilizing a fixed-dose paradigm and a 12-week primary endpoint. The company anticipates initiating the new trial in the fourth quarter of 2025.

CEO Herriot Tabuteau said that the company is “well-positioned” to initiate the new trial.

Fibromyalgia is a chronic disorder characterized by widespread pain, fatigue, disturbed sleep, depression, and cognitive impairment. Approximately 17 million Americans, 90% of whom are women, are estimated to suffer from the disorder.

On Stocktwits, retail sentiment around Axsome stayed unmoved within the ‘bullish’ territory over the past 24 hours while message volume stayed at ‘high’ levels.

AXSM's Sentiment Meter and Message Volume as of 8:05 a.m. ET on June 9, 2025 | Source: Stocktwits


A Stocktwits user opined that the possibility for the company achieving profitability by the end of the year is “out the window.”

Another user, however, brushed it off as a “small delay.”

AXSM stock has risen by about 28% this year and by about 56% over the past 12 months.

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